Liquid refrigerant control means for refrigerating systems



Feb-k 1933. E. A. VON SEGGERN ET'AL 1,898,277

LIQUID REFRIGERANT CONTRQLMEANS FOR REFRIGERATING SYSTEMS Filed Oct. 6,1950 INVENTORS ERNESTA- v0 SEGGER/V BYHENRYE. va/v SEGGERN AT'i'O NEYPatented Feb. 21, 1933 UNITED STATES rA'rE r orrlca ERNEST A. vonsneemm, or Los memes, Aim HENRY r. Von SEGGERN, or

ns'oonmno, CALIFORNIA LIQUID REFRIGERANT CONTROL MEANS FOR REFRIGERATINGSYSTEMS Application filed October 6, 1930. I Serial No. 486,574.

Our present invention relates to meanscontrolling the liquid refrigerantin refrlgerating systems when desiring to sterilize the evaporator. Y e

In certain kinds of liquid. refrigeration, the liquids are cooled byallowing the same to flow over the evaporator of the system,particularly in systems where the evaporator isarranged in the form ofan expansion coil. For sanitary reasons, it becomes necessary tosterilize the evaporator frequently. This is usually accomplished bydirecting a spray of steam from a. boiler against the evaporator. Inorder that the steam may quickly heat the evaporator to the requiredtemperature for sterilizing the coil, it is absolutely necessary thatthe liquid refrigerant be first removed from the evaporator. If this isnot done, sufficient heat must be supplied to the evaporator that thepressure therein (in am monia systems) rises. to a pressure of over ninehundred pounds per square inch in order to raise the temperature of theevaporator coils to a sterilizing temperature of about two hundredtwelve degrees. In practice, the liquid refrigerant is first pumped fromthe evaporator by closingthe expansion valve and operatingthe'compress'or until the liquid has boiled out of the evaporator, afterwhich the evaporatormay be easily heated by steam.

Our present invention and in refrigerating systems dispens'es'with thenecessity of pumping the liqnidrefrigerant from the evaporator or thecreation of such pressures. 4 f o "An important object of ourinventionis to provide means for removing or receiving the liquidrefrigerant from the evaporator soon after the compressor has beenstopped and keeping it out of the evaporator during the sterilizationprocess and until the compressor is started again, and for normallyretaining the liquid refrigerant in the evaporator as long as thecompressor is in operation;

Another important object of our invention is to provide such meanswhich, in certain forms, is entirely automatic' in its action andrequires no atte'fition whatsoever. I

A further object is to provide a novel and simple means for storingth'eliquid refrigimprovements erant, normally containedin the evaporator,during sterilization of the evaporator.

A still further object of our invention is to provide simple means formaintaining the temperature of the liquid refrigerant storage chamber atthe desired temperature whereby the liquid refrigerant is normallyforced into i the evaporator, and to provide such temperaturemaintaining means which cooperate with the evaporator of the system andforms a pr'e-cooling means therefor.

Another object of this invention is to provide liquid refrigerantcontrol means of the class 'mentioned which is simple and economical ofconstruction, installation, and operation, and which will notreadilydeterio rate or get out of order.

With these and other objects in view as will appear hereinafter, we haveprovided av refrigeration system having certain novel 7 features ofconstruction, combination and arrangement of parts and portions, aswillbe hereinafter described in detail and particularly set forth in theappended claims, reference being had to the accompanying drawing I andto the characters of reference thereon which form a part of thisapplication in which; I

. The figure; of the drawing is a fragmentary and diagrammaticelevational View. of a refrigerating system embodying our invention.

'Dhe refrigerating system illustrated in the drawingis one form ofcooling apparatus for cooling such product as milk, and which, it isnecessary, to-sterilize frequently; In this apparatus the milk isdischarged into a distributor-l from a tank 2 or other sourceof supply.From the distributor 1, the milk is. directed. downwardly, by gravity ifdesired, over a'pre-cooling coil and then over a final, c-ooling'coil.The pre;cooling coil 3 is positioned immediately below thedistributorand "immediately above the final cooling coil 4.

From the coil 4, the cooled milk drops into tor 7 which is alsoconnected at its bottom end by a conductor 8 to the lower portion of theevaporator. The upper end of the ,ac-

'cumulator 7 is connected by a conductor 9 to the suction end of thecompressor 10. The

discharge-end or high pressure side of the compressor is connected to areceiver 11 in which the compressed refrigerant is liquefied. Thereceiver is also connected by a conductor 12 to the lower portion of theevaporator and of the accumulator through the conductor 8. In theconductor 12 is interposed an expansion valve 13 which, in thisinstance, is a hand controlled valve.

To the lower portion of the evaporator and the accumulator, andpreferably to the conductor 8, which is connected with such portions ofthe evaporator and the accumula-v tor, is connected the lower portion ofa drum or receptacle 14, by means of a conductor 15. Between theconductor 15 and the receptacle 14 is interposed a trap 16. Theconductor 15 and the trap 16 are so positioned with respect to the lowerportion of the evaporator that all liquid refrigerant in the latter andin the accumulator is adapted to flow by gravity into the conductor 15and the trap 16 and from the latter into the receptacle 14'which will beherein known as the liquid refrigerant storage chamber. The liquidrefrigerant is received and stored'in the receptacle 14 when thepressure in the evaporator 4 exceeds the pressure in the receptacle 14.

The receptacle 14 or liquid refrigerant storage chamberis enclosed by acasing 17 which forms a water jacket therefor. This Water jacket iscontinually supplied with water through a conductor 18 which extendsfrom a pump 19 to the upper end of the water jacket. The upper end ofthe water jacket is also connected by a conductor '20 to the lowerportion of the pre-cooling coil 3. Thus it will be seen that the pipesor conductors are so connected to the jacket that the cooling liquid inthe jacket will not be siphoned therefrom. The upper portion of the coil3 may be connected by a conductor 21 to a cooler, not shown. The waterfrom such a cooler may be the source of water for the pump'19. The waterpassed through the water j acket 17 is at a temperature less than roomtemperature so that when the compressor is stopped and the evaporator 4heated to room temperature, the pressure in the evaporator will begreater than that in the liquid refrigerant storage chamber 14 and forcethe liquid refrigerant into the storage chamber.

The operating principle of our invention in the refrigerating system isthe direct relation which exists between the vapor pressure ofarefrigerating fluid and its temperature. When the compressor is inoperation and a quantity of liquid is in the evaporator, there is a flowof vapor through the suction line 9 to the compressor and a flow ofliquid refrigerant from the receiver 11 through the expansion valve 13to the evaporator, replenishin the li uid refrigerant therein whichbolls off during the process of refrigerating. During normal operationof the system, there is no liquid refrigerant inthe receptacle 14, thevapor pressure therein being the same as that in the accumulator. Thetemperature of the liquid refrigerant in the evaporator must, for normaloperation, be less than that of the cooling water in the water jacket17. If, during normal operation, any liquid refrigerant passes thereceptacle 14, it will vaporize and attempt to produce a vapor pressurein this receptacle which corresponds to the temperature of the waterin'the water jacket, forcing any liquid refrigerant from the receptacle14 through the trap 16 into the conductor 15 and into the evaporator andaccumulator.

' When the compressor is stopped, the valve 13 is closed manually. Sincethe evaporator and the suction line 9 are exposed to room temperature,the liquid in the evaporator will boil until the pressure in theaccumulator and suction line will correspond to such higher temperature.Due to the water trapped in the jacket 17 the liquid refrigerant storagechamber 14 will still be at the same temperature as when the machine wasin operation, and since the cooling water is assumed to have atemperature lower than that of ordinary room temperature, the vaporpressure in the chamber is now less than that in the evaporator,accumulator, or suction line, the liquid refrigerant in the evaporatoris forced into the storage chamber, which is of a size sufiicient tohold substantially all of the liquid refrigerant in the evaporator andaccumulator. The liquid refrigerant will remain in the chamber 14 aslong as the vapor pressure therein is less than in the evaporator,accumulator, or suction line. The evaporator or coil 4 may then besterilized with steam without creating excessive pressures in thesystem.

When the compressor is again started, the pressure in the evaporator,accumulator and suction line is reduced, and, when this pressure fallsbelow that normally maintained in the storage chamber, the liquidrefriger- I ant is forced from the storage chamber back into theevaporator, and the system is again ready for normal operation, andafter the valve 13.is reopened.

Our liquid refrigerant control means herein disclosed may be used with arefrigerating system employing an automatic float-type expansion valve,provided a shutoff is opened and closed in the liquid line from thereceiver when the compressor is started and shut down. The handcontrolled expansion valve may be set for normal op struction,combination and arrangement, nor

to the particular application, but desire to include in the scope ofourinvention the construction, combination and arrangement substantiallyas set forth in the appended claims. Having thus described ourinvention, what we claim as new and desire to secure by Letters Patentis. 4 1. In a refrigeration system, an evaporator adapted to containliquid refrigerant, means for receiving the evaporated refrigerant fromthe upper portion of the evaporator and for compressing and supplyingthe same to the lower portion of the evaporator, a liquid refrigerantstorage chamber communicating with the lower portion of the evaporatorand adapted to receive the liquid refrigerant therefrom when thepressure in the evaporator becomes excessive, awater;

jacket surrounding said chamber, means for supplying cooling water tothejacket, and a pro-cooling means inassociation with the evaporator andconnected to and adapted to receive the water from the jacket. I

2. .In a refrigeration systemfan evaporator adapted to contain ,liquidrefrigerant, means for receiving evaporated refrigerant fromthe upperportion of the evaporator and for com+ pressingthe same, a receiver forreceiving the liquefied refrigerant from the last mentioned means andconnected to the lower portion of the evaporator, a valve interposed inthe connection between the receiver and the evaporator, a liquidrefrigerant storage chamber communicating with the Power portion ofthe/evaporator and adapted to receive the liquid refrigerant therefromwhen the pressure in the evaporator becomes excessive,

*a water jacket surrounding said chamber,

means for supplying cooling water to the jacket, and a pre-cooling meansin association with the evaporator and connected to and adaptedtoreceive the water from the acket.

3. In a refrigerating system, an evaporator adapted to contain liquidrefrigerant, an

accumulator connected at its upper portion with. the upper portion ofthe evaporator and j at its lower portion with the lower portion of theevaporator, means for receiving evaporated refrigerant from theaccumulator and for compressing the same, the latter means beingconnectedwith the lower portion of the evaporator, a liquid refrigerantstorage chamber communicating with the lower portipns ofthe accumulatorand evapsurrounding the chamber, a liquid supply' for the jacket, andmeans connecting t e jacket to the-pre-cooling coil. c

5. In a refrigerating'system, an evaporator, a pre-cooling coil arrangedabove the evaporator and adapted for pre-cooling liquid directed overthe evaporator, a liquid refrigerant storage chamber communicating withthe evaporator and adapted to receive substantially all of theliquidrefrigerant contained therein, av liquid cooling jacket surroundin thechamber, a, cooling liquid supply con uctor connected to the upperportion of the jacket, and another conductor connecting the upperportion of the jacket to the lower portion of the pracooling coil. 6.Inarefrigerating system, a pre-cooling coil, an evaporator coilpositioned below the former, means for supplying liquid to be cooled 'tothe upper portion of the pre=cooling coila (iompressor'connected withthe upper portion of the evaporator coil and connected at its pressureside to the lower portion of the eva orator coil, a valve between thepressure side of the compressor/and the, evaporator coil, a liquidrefrigerant storage chamber a cooling jacket surrounding the storagechamber, means for su plying a cooling liquid to the jacket, a con uctorconnect; ing thejacket to the lower portion of the precooling coil, andatiischarge for the pres-cools ingcoil. T v

7. Ina refrigeration system, a pre-cooler,

'an evaporator ada ted to contain liquid; re-

frigerant, meansfor receiving the evaporated refrigerant from the upperportion ofthe evaporator and for compressing and supplying the same tothe lower portionof the evaporator, a liquidrefrigerant storage chambercommunicating with the lower portion of the evaporator and adapted toreceive the liquid refrigerant therefrom when the pressure in theevaporator becomes excessive, a water jacket surrounding said chambermeans connecting said ,water jacket, w th said precooler, and means forsupplying cooling water to the jacket.

8. In a refrigeration system, a pre-cooler, an evaporator ada ted tocontain'liquid refrigerant, means or receiving evaporated refrigerantfromfthe upper portion of the evaporator and for compressing the same, areceiver for receiving the liquefied refrigerant from the last mentionedmeans and connected to the lowerportionof the evaporator, a valveinterposed in the connection between the receiver and the evaporator,aliquid refrigerant storage chamber com- I municating with thelowerportion of the evaporator and adapted to receive the liquidrefrigerant therefrom when the pressure in the evaporator becomesexcessive, a water jacket surrounding said chamber means connecting saidwater .jacket with said precooler, and means for supplying cooling waterto the 'acket.

9. In a re rigerating system, a pre-cooler,

an evaporator adapted to contain liquid re-- frigerant, an accumulatorconnected at its upper portion with the upper portion of the evaporatorand at its lower portion with the lower portion of the eva orator, meansfor receiving evaporated re rigerant from the accumulator and forcompressing the same,

the latter means being connected with the lower portion of theevaporator, a liquid refrigerant storage chamber communicating with thelower portions of the accumulator tor, a cooling coil, a liquidrefrigerant storage chamber communicating with the evaporator andadapt-ed to receive substantially all of the liquid refrigerantcontained therein, a liquid cooling container means associated with saidchamber, a liquid supply-for the container means, and means connectingthe container means with the cooling coil.

12. In a refrigerating system, an evaporator, a pre-cooling coil, aliquid refrigerant storage chamberv communicating with the evaporatorand adapted to receive substantially all of the liquid refrigerantcontained therein, a liquid cooling jacket surrounding the chamber, aliquid supply for the jacket, and means connectingthe jacket to theprecnoling coil.

13. In a refrigerating system, an evaporator, a pro-cooling coil, aliquid refrigerant storage chamber communicating with the evaporator andadapted to receive substantially all of the liquid refrigerant containedtherein, a liquid cooling jacket surrounding the chamber, a coolingliquid supply conductor connected to the upper portion of the jacket,and another conductor connecting the upper portion of the jacket to thelower portion of the pre-cooling coil.

In testimony whereof, we have hereunto set our hands, respectively, atLos Angeles, California, this 29th day of September, 1930, and atEscondido, California, this 25th day of September, 1930.

ERNEST A. VON SEGGERN. HENRY E. vo'N SEGGERN.

